Catalysts for the polymerization of olefins to yield predominantly dimers and trimers



United States Patent 3,475,347 CATALYSTS FOR THE POLYMERIZATION 0FOLEFINS T0 YIELD PREDOMINANTLY DIMERS AND TRIMERS Burnett H. Johnson,Baytown, Tex., assignor to Esso Research and Engineering Company NoDrawing. Filed Nov. 16, 1966, Ser. No. 594,682 Int. Cl. B011 11/00,11/78 US. 'Cl. 252-429 7 Claims ABSTRACT OF THE DISCLOSURE Lower olefinsare polymerized to oligomers by a Friedel-Craft type catalyst systemconsisting of a first component selected from a compound having theformula:

RMeX or R MeX where: R is a lower alkyl group, e.g., C to C X is Cl, Br,or I, and Me is Al, Ga or In; and the second component is according tothe Mendeleev Periodic Table a Group I-B, IIB, or IVB metal halide orbinary compound of the metal halide with AlCl GaCl or InCl The presentinvention is directed to a catalyst of the Friedel-Craft type for thepolymerization and copolymerization of olefins to produce low molecularweight compounds. More particularly, the invention is directed to acatalyst system consisting of two components which produces primarilydimers, trimers, and tetramers of olefins.

The present invention may be briefly described as a Freidel-Craft typecatalyst system consisting of a first component selected from a compoundhaving the formula:

RMeX or R MeX Where: R is a lower alkyl group, e.g., C to C X is Cl, Br,or I, and Me is Al( Ga or In; and the second component is according tothe Mendeleev Periodic Table a Group IB, II-B, or IV-B metal halide orbinary compound of the metal halide with AlCl GaCl or InCl While thecatalyst system of the present invention has been characterized as ofthe Friedel-Craft type, the catalyst system of the present invention hashigher activities at moderate temperatures and pressures than knownFriedel-Craft type catalysts. Further, the catalysts of the presentinvention are more selective to particular isomers, not necessarily themost stable thermodynamically, than is the case with most Friedel-Craftcatalysts. One unusual property of the catalyst system of the presentinvention is the ability to produce straight chain dimers and trimerswhich involves reaction other than just the double bond.

The catalyst of the present invention will polymerize the lower olefinsto the dimer, trimer, and tetramer. The lower olefins are illustrated bythe C to C straight and branched chain monolefins such as ethylene,propylene, butene-l, cis and trans butene-Z, isobutene, etc. Alsomixtures of the lower olefins may be copolymerized.

The first component of the catalyst system of the present invention maybe illustrated by methyl-aluminum dichloride, dimethyl aluminumchloride, ethyl-aluminum dibroinide, dibutyl aluminum chloride, diethylaluminum iodide, methylgallium dichloride, ethylindium dichloride, etc.Preferably the first component is an alkyl aluminum dichloride ordialkyl aluminum chloride; however, the monoalkyl aluminum dihalide ismore reactive.

The second component of the catalyst system may be exemplified by CuX,CuX AgX, ZnX CdX HgX, HgX SnX SnX PbX CuMeX AgMeX ZnMe X and PbMe Xwhere X is Cl, Br or I and Me is Al, Ga or In. While each of the secondcomponent compounds of the catalyst system yields a straight chaindimer, the partic- 3,475,347 Patented Oct. 28, 1969 ular selection wouldbe based on the specific isomers desired. For example in thedimerization of propylene, the catalyst system of the present inventionyields with high activity trans -4-methyl-2-pentene in greater abundancethan either 2-methyl-1-pentene or Zunethyl-Z-pentene, both of which aremore favored thermodynamically.

The components of the catalyst system of the present system may becombined and used in their pure state or preferably are dispersed in aninert saturated hydrocarbon diluent. Parafiin diluents such as hexane,heptane, octane, isooctane, cyclohexane and the like are suitable. Thecomponents are combined so that the mo] ratio of the first component tothe second component is equal to or greater than one. The mol ratio maybe three to one; however, a ratio of one to one is suitable.

The dimerization reaction may be carried out at reaction temperatures of0 C. to 150 C. The pressure of the reaction system in the dimerizationof the normally gaseous olefins is between 0.1 to atmospheres. However,room temperature and one atmosphere pressure are suitable. When normallyliquid olefins are dimerized, the liquid olefin may be reacted inconcentrations as low as 1%, although it is preferred to use higherconcentrations, preferably 50% or higher.

The invention will be further illustrated by the following specificexamples which are given by way of illustration and not as limitationson the scope of the invention.

EXAMPLE 1 Mol percent 2-methylpentane 1.3

4-methyl-1-pentene 1.0 Cis-4-methyl-2-pentene 4.5Trans-4-methyl-2-pentene 30.4 2-methyl-l-pentene 0.6 2-methyl-2-pentene29.9 Normal-hexenes 27.4

EXAMPLE 2 The conditions were the same as Example 1, except (C H AlC1was used instead of (C H )AlCl The product analyzed as follows:

Mol percent 4-methy1-1-pentene 2.7

Cis-4-methyl-2-pentene 6.7 Trans-4-methyl-2-pentene 49.0Z-methyl-l-pentene 2.7 2-rnethyl-2-pentene 10.8 Normal-hexenes 28.1

EXAMPLE 3 The conditions were the same as Example 1, except CuCl wasused instead of CuAlCl The results are given below:

Mol percent 4-methyl-1-pentene 1.5 Cis-4-methyl-2-pentene 5.7Trans-4-methyl-2-pentene 33.5 Z-methyl-l-pentene 2.9 2-methyl-2-pentene24.1 Normal-hexenes 32.3

3 EXAMPLE 4 The conditions were the same as Example 1, except AgAlCl,was used instead of CuAlCl The analysis of the product is given below:

Mol percent 4-methyl-1-pentene 1.4 Cis-4-methyl-2-pentene 5.7Trans-4-methyl-2-pentene 39.8 2-methyl-1-pentene 1.9 2-methyl-2-pentene29.2 Normal-hexenes 22.0

EXAMPLE 5 The conditions were the same as Example 1, except ZnAl CI wasused instead of CuAlCl The product analysis is given below:

Mol percent 4-methyl-1-pentene 1.9 Cis-4-methyl-2-pentene 11.2Trans-4-methyl-2-pentene 60.8 2-methyl-1-pentene 0.0 2-methyl-2-pentene0.0 Normal-hexenes 26.1

EXAMPLE 6 The conditions were the same as in Example 1, except PbAl Clwas used instead of CuAlCl The product distribution was as follows:

Mol percent 4-methyl-1-pentene 15.5 Cis-4-methyl-2-pentene 7.3Trans-4-methyl-2-pentene 26.7 2-methyl-1-pentene 2.5 2-methyl-2 pentene2.5 Normal-hexenes 45.5

EXAMPLE 7 A catalyst comprising 0.1 gm. of CuCl plus 0.12 gm. of (C H)AlCl in 5 ml. of isooctane were introduced into a flask with stirrer atC. An atmosphere of a 50-50 mol percent mixture of propylene andethylene was added (760 mm. of Hg) and reaction took place. The productwas analyzed and found to be approximately 29.6% C 57.9% C and 12.5% Cwith small amounts of C The C fraction was predominately linear butenes.

By the foregoing example, the predominance of C illustrates thecopolymerization which will occur with mixtures of lower olefins.

EXAMPLE 8 A catalyst comprising 0.1 gm. of AgAlCl plus 0.12 gm. of (C H)AlCl in 5 m1. of isooctane were introduced 4 into a flask at 25 C. andstirred. An atmosphere of ethylene was added and a rapid reactionoccurred. The product was analyzed and found to be 77% C 21% C and 2% CThe nature and objects of the present invention having been fullydescribed and illustrated, what I wish to claim as new and useful andsecure by Letters Patent is:

1. A catalyst consisting of:

a first component selected from a compound having the formula:

RMeX and R MeX Where: R is a lower alkyl, Me is Al, Ga or In and X isCl, Br, or I; and

a second component selected from the binary compounds of a member of thegroup consisting of group I-B, II-B, and IV-B metal halides with amember of the group consisting of AlCl GaCl and InCl said firstcomponent and second component being combined such that the mole ratiois between 1:1 and 3:1. 2. A catalyst of claim 1 wherein Me is Al and Xis Cl in said first component.

3. A catalyst of claim 1 wherein said second component is CuAlCl 4. Acatalyst of claim 1 wherein said second component is AgAlCl 5. Acatalyst of claim 1 wherein said second component is ZnAl Cl 6. Acatalyst of claim 1 wherein said second component is PbAl Cl 7. Acatalyst of claim 2 wherein said second component is selected from thegroup consisting of CuAlC1 AgAlCl ZnAl Cl and PbAI Cl References CitedUNITED STATES PATENTS 2,993,035 7/ 1961 Christman 26094.3 3,128,252 4/1964 Tornqvist 252429 3,121,063 2/1964 Tornqvist 252-429 3,001,9518/1961 Tornqvist 252-429 2,914,520 11/ 1959 Vandenburg 26094.9

FOREIGN PATENTS 617,652 4/1961 Canada.

PATRICK P. GARVIN, Primary Examiner PHILIP M. FRENCH, Assistant ExaminerUS. Cl. X.R.

